What is everyone's opinion on lightweight flywheels?

[FORSFED]

I'm a little unsure about how much I like the aluminum Fidanza flywheel I have in my car and wanted to hear what others opinions are who have run them in their cars.

The one thing I do like about it is that the motor does rev extremely quick. But, I think a lot of that also has to do with my lightweight and fully balanced rotating assembly as well.

Things I don't like about it are when I come to a quick stop the engine usually kills and upon coming to a normal stop, the engine will rev up to like 1500 and hang there for a few seconds before coming back down to a normal idle. Has anyone else experienced anything like this or is it just me? Is there a way I can tune this out? Any other suggestions or opinions? Ultimately I'm debating on whether or not to use a stock one again...

[JET]

Yeah, I think the fidanza is a little too light for a car without balance shafts. It depends on the application though, for autox it would be fine, but normal driving it makes lauching more difficult. The ACT seems to be a good mix, but the Fidanza seems to have a better surface for higher HP cars and it is replaceable.

[Jakey]

Are you still running a stock ECU? What is your idle set to? You may find this thread on Tooners to be quite interesting as it is in regards to the stalling issue you are also running into: http://www.dsmtuners.com/forums/showthread.php?t=158190&page=1&pp=25

Also, From what I've been reading (yes reading, not personal experience), the SSG is a great option for a flywheel.

[carltalon]

I'm running the ACT and have pretty mutch the same symptoms when slowing down or stopping. I can usually keep the car from stalling if I wait till the last second to push the clutch in before comeing to a stop.

[MustGoFaster]

I have a fidanza, and none of the issues you guys describe. I like it.

[At-Least-It's-An-Evo]

I had the ACT and had no issues you guys speak of also. I wasn't able to tell a difference in drivability.

[1ViciousGSX]

I have the Fidanza billet flywheel.

Light flywheels are a "give to get" kind of thing. You will give up some drivability issues with launching and possibly have low idle stalls when pushing in the clutch too soon, but once your car is lauched, you should see an improvement. The less power it takes to turn the flywheel is more power getting to the ground. This would only apply to hard acceleration though.

[Sean485]

I have a fidenza 8lb flywheel and no balance shafts, I've only ever had the car stall on me once just from pushing the clutch in and the car had a mis from bad plug wires so that certainly didnt help. Otherwise the only time I notice it is just around traffic driving that i have to make sure to keep the rpms up a bit more leaving from a stoplight when i'm slipping the clutch. Launching I cant really say if there is a huge difference because I have tires that just spin when I launch, a stutter box and my stock clutch wouldnt let me launch before because it slipped so bad.

[Alpine TSi]

I like my ACT, I have noticed the RPMs hang longer between shifts, and that is all that matters to me.

[A//// Guy]

Wow I didnt know this many people had lightened flywheels. Is it really worth the few extra horses? Sure there are a few gained but is the price justifyable? Just curious if anyone has a dyno camparison. I would only thing between shifts keeping the rpms up would help, but if you have NLTS then theres no gain.

I agree that less weight = more power, especially rotating weight but Im curious as to how much is gained and what are the disadvantages of just runing a stock flywheel?